CHLORMADINONE ACETATE, A NEW HIGHLY ACTIVE GESTATION-SUPPORTING AGENT

Abstract

Chlormadinone acetate was submitted to a battery of biological test procedures, and its endocrinological actions were compared with those of progesterone and medroxyprogesterone acetate. It is a highly active oral progestational agent, being 10 times as active as any presently available compound. Chlormadinone also is as effective in maintaining pregnancy in ovariectomized rabbits as medroxyprogesterone acetate. Although the compound is a strong anti-estrogen, it is a weak gonadotrophin inhibitor when compared with medroxyprogesterone acetate by the classical procedures. The compound does possess adrenal suppressive potential, which is somewhat less than that exerted by medroxyprogesterone acetate.